Pola

POLA, a seaport of Italy, the capital of the province of Pola, in the district of Venezia Giulia, 86 m. S. of Trieste by rail. Pop. (1931), 41,638 (town), 55,559 (commune). It was the principal naval harbour and arsenal of the Austro-Hungarian monarchy until 1918, and is situated near the southern extremity of the pen insula of Istria. It lies at the head of the Bay of Pola, and possesses a safe and commodious harbour almost completely land locked. An extensive system of fortifications, constructed on the hills which enclose the harbour, defends its entrance, while it also possesses a good roadstead in the large channel of Fasana. The modern town of Pola lies round the base of a hill formerly crowned by the Roman capitol, and now by a castle of the 17th century. Besides the castle the chief buildings are the cathedral, burnt down in 1923 and reconstructed on the lines of a 6th cent. Ravenna basilica ; the new garrison church, completed in 1898 in the basilica style, with a marble façade; and the Franciscan church dating from the 14th century. To the south-west, along the coast, extends the marine arsenal, which has now been dis mantled ; the large barracks are equally deserted. The chief inter est of Pola centres in its fine Roman remains. The most extensive of these is the amphitheatre built in A.D. 9 in honour of the emperors Septimius Severus and Caracalla, which is 79 ft. high, 400 ft. long and 320 ft. wide, and could accommodate about 23,000 spectators. It is remarkable as the only Roman amphi theatre of which the outer walls have been kept intact. The history of Pola begins with its capture by the Romans in 178 B.C. It was destroyed by Augustus on account of its espousal of the cause of Pompey, but was rebuilt under the name of Pietas Iulia, and was mainly important as a harbour. Later it became the capital of the margraves of Istria, and was captured by the Venetians in 1148. In 1379 the Genoese, after defeating the Vene tians in a great naval battle off the coast, took and destroyed Pola, which disappears from history for the next four hundred and fifty years. It remained under Venetian supremacy down to 1797, and fell under Austria in 1815.

See T. G. Jackson, Dalmatia, the Quarnero and Istria, vol. iii. (5887). POLABS (Po-=on, Laba=Elbe), the Slays (q.v.) who dwelt

upon the Elbe and eastwards to the Oder. Except the Lithuanians they were the last Europeans to be Christianized; their chief sanctuary was at Arcona on the Isle of Riigen. They were con verted and conquered in the 12th century and Germanized. By the 17th century Slavonic survived only in a tiny patch in the east of Hanover about Liichow ; its scanty remains are corrupt. POLAND (PoLsKA), an independent republic, formally con stituted on March 21, 1921, out of territories which had belonged since 1815 to Prussia, Austria and Russia. The northern, western and southern frontiers, marching with Germany, Czechoslovakia and Rumania, were fixed, mainly on ethnological principles, by the Treaty of Versailles. The north-east and eastern frontiers march with the frontiers of Lithuania, Latvia and the Soviet Union, and were determined by political and historical as well as ethnological considerations after the Treaty of Riga.

Geology.

The oldest rocks in the country outcrop in the south, forming the Lysa Gora, slightly to the east of Kielce. They form part of the Palaeozoic platform, often known as "the Polish plat form," against which the younger Carpathian fold mountains to the south were niched up. The general south-east to north-west trend of the fold mountains was turned first to east and west and then, with further resistance from the Bohemian mass, almost north-east to south-west. The plateau of Tarnowice and other regions in the two provinces of Piotrkow and Kielce have Triassic, Jurassic and Cretaceous outcrops. The south-eastern sec tion of the country has extensive Cretaceous outcrops centred around Lublin. These are interspersed by Tertiary rocks, par ticularly in the neighbourhood of Lwow. The valleys of the Upper Dniester and Vistula have Quaternary material, while on the northern slopes of the Carpathians, and in Galicia generally, there are deposits of fertile loess—a factor potent in the history and early settlement of the region. The entire northern section of the country has a covering of boulder clay, containing much marsh land and myriads of small shallow lakes. The extensive Pripet marshes on the east of Poland, near Pinsk, have played a very important part in differentiating Poland and Russia.